ensure that numpy is not imported on startup

[williamstein]

This might or might not be worth it. Numpy is actually pretty fast these days (<.05 seconds), and the work needed to not import it is pretty scary. The attached patch causes all kinds of subtle trouble.

---

Apply only attachment: trac_11714-only-this.patch to the Sage library.

Component: misc

Keywords: sd32

Author: William Stein, Julian Rueth

Reviewer: William Stein

Merged: sage-4.7.2.alpha3

Issue created by migration from https://trac.sagemath.org/ticket/11714

[williamstein]

Description changed:

--- 
+++ 
@@ -1 +1 @@
-
+This might or might not be worth it.  Numpy is actually pretty fast these days (<.05 seconds), and the work needed to not import it is pretty scary.  The attached patch causes all kinds of subtle trouble.   

[williamstein]

comment:1

Attachment: trac_11714.patch.gz

[williamstein]

Changed keywords from none to sd32

[saraedum]

Attachment: trac_11714_numpy_startup.patch.gz

use lazy imports to make sure numpy is not loaded on startup

[saraedum]

comment:3

With the last patch numpy is not loaded in ./sage and ./sage --startuptime. Surprisingly this doctest fails, i.e., numpy is loaded in the doctests.

sage: import sys 
sage: 'numpy' in sys.modules 
False

I'll post something about the startup improvement once the full doctest run finished.

[williamstein]

comment:4

This passes "make ptestlong" for me, except for the issue with 'numpy' in sys.modules.

I thought I posted how to fix this last night, but maybe there was a network problem. One solution is to use the Sage pexpect subprocess. I'm refreshing your patch with that.

[williamstein]

fixes the import numpy issue. make ptestlong passes.

[williamstein]

comment:5

Attachment: trac_11714-only-this.patch.gz